Pub Date : 2024-05-03DOI: 10.1007/s00107-024-02082-2
Grzegorz Struzikiewicz, Marek Misiniec, Kinga Misiniec, Anna Myrda
Making furniture or furniture elements that account for the needs of children at various stages of development or with psychomotor dysfunctions is very difficult. From the point of view of exploitation and production technology, it is difficult to select a specific material and manufacturing technique. In this article, the results of using the APEKS method, which is a type of Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, are presented to select the best solution for the production of children’s furniture elements with surface structures similar to those of natural materials. Wood bark was selected as a material that, due to the sensory tactile sensations of dysfunctional children, could contribute to therapy and education. Comparative analysis was performed on the basis of the subtractive and additive methods used for manufacturing furniture products. Precise multiaxis milling of ash wood and 3D printing with fused filament fabrication technology using wood PLA filaments were carried out. The method used to select the best option considered quantitative and qualitative criteria in the assessment. Various parameters characterizing the surfaces were analyzed, such as geometric dimensions, hill heights, valley depths, and 3D surface parameters. The quality and surface roughness (Sa, Sz, Ssk, Sku, Sp, and Sv) parameters obtained based on 3D microscope measurements were determined. A scale of 1 to 10 was used to assess qualitative factors (i.e., usability and aesthetics). Based on the critical values obtained from the coefficient Kcri = 79.36, it was assumed that multiaxis wood milling was the best method for producing furniture elements with the required surface characteristics for use as therapeutic and educational tools for children with dysfunctions. The applied method allowed an effective evaluation of the compared variants of the production of furniture elements for customized applications.
{"title":"Application of the TOPSIS decision-making method for selecting a manufacturing technique for children’s furniture elements with therapeutic functions","authors":"Grzegorz Struzikiewicz, Marek Misiniec, Kinga Misiniec, Anna Myrda","doi":"10.1007/s00107-024-02082-2","DOIUrl":"https://doi.org/10.1007/s00107-024-02082-2","url":null,"abstract":"<p>Making furniture or furniture elements that account for the needs of children at various stages of development or with psychomotor dysfunctions is very difficult. From the point of view of exploitation and production technology, it is difficult to select a specific material and manufacturing technique. In this article, the results of using the APEKS method, which is a type of Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, are presented to select the best solution for the production of children’s furniture elements with surface structures similar to those of natural materials. Wood bark was selected as a material that, due to the sensory tactile sensations of dysfunctional children, could contribute to therapy and education. Comparative analysis was performed on the basis of the subtractive and additive methods used for manufacturing furniture products. Precise multiaxis milling of ash wood and 3D printing with fused filament fabrication technology using wood PLA filaments were carried out. The method used to select the best option considered quantitative and qualitative criteria in the assessment. Various parameters characterizing the surfaces were analyzed, such as geometric dimensions, hill heights, valley depths, and 3D surface parameters. The quality and surface roughness (Sa, Sz, Ssk, Sku, Sp, and Sv) parameters obtained based on 3D microscope measurements were determined. A scale of 1 to 10 was used to assess qualitative factors (i.e., usability and aesthetics). Based on the critical values obtained from the coefficient <i>K</i><sub><i>cri</i></sub> = 79.36, it was assumed that multiaxis wood milling was the best method for producing furniture elements with the required surface characteristics for use as therapeutic and educational tools for children with dysfunctions. The applied method allowed an effective evaluation of the compared variants of the production of furniture elements for customized applications.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-03DOI: 10.1007/s00107-024-02079-x
Salvio Marino, Milan Gaff, Anil Kumar Sethy, Gourav Kamboj, Fatemeh Rezaei, František Kačík, S. Behnam Hosseini, Haitao Li, David Hui
The increasing demand for wood with enhanced flame retardant characteristics in construction applications necessitates strategic interventions. This study explores the fire behaviour and chemical characterisation of Robinia pseudoacacia wood subjected to thermal modification and flame retardant treatments. Thermal modification was carried out at three different temperatures (160 °C, 180 °C and 240 °C). The fire properties of wood coated with Flame Gard (F), a commercial flame retardant, arabinogalactan (A), a natural flame retardant, melamine adhesive (MF) with ammonium polyphosphate (AP), nanosilica (NS), nanoclay (NC) (MF-AP-NS and MF-AP-NC) and arabinogalactan with AP, NS and NC (A-AP-NS and A-AP-NC), were assessed using cone calorimetry in terms of the weight loss rate, ignition time and heat release rate. The commercial flame retardant Flame Gard outperformed the natural and fortified flame retardants in terms of the weight loss rate, heat release rate (HRR) and ignition time (tig). Unmodified samples exhibited superior fire properties in terms of tig and HRR compared to thermally modified samples. The peak heat release rate (kW.m− 2) and time to peak heat release rate (s) showed a moderate degree of dependency on the chemical constituents of the wood.
{"title":"Enhancing the fire resistance properties of thermally modified Robinia pseudoacacia wood with natural and synthetic flame retardants: chemical characterisation and fire behaviour","authors":"Salvio Marino, Milan Gaff, Anil Kumar Sethy, Gourav Kamboj, Fatemeh Rezaei, František Kačík, S. Behnam Hosseini, Haitao Li, David Hui","doi":"10.1007/s00107-024-02079-x","DOIUrl":"https://doi.org/10.1007/s00107-024-02079-x","url":null,"abstract":"<p>The increasing demand for wood with enhanced flame retardant characteristics in construction applications necessitates strategic interventions. This study explores the fire behaviour and chemical characterisation of <i>Robinia pseudoacacia</i> wood subjected to thermal modification and flame retardant treatments. Thermal modification was carried out at three different temperatures (160 °C, 180 °C and 240 °C). The fire properties of wood coated with Flame Gard (F), a commercial flame retardant, arabinogalactan (A), a natural flame retardant, melamine adhesive (MF) with ammonium polyphosphate (AP), nanosilica (NS), nanoclay (NC) (MF-AP-NS and MF-AP-NC) and arabinogalactan with AP, NS and NC (A-AP-NS and A-AP-NC), were assessed using cone calorimetry in terms of the weight loss rate, ignition time and heat release rate. The commercial flame retardant Flame Gard outperformed the natural and fortified flame retardants in terms of the weight loss rate, heat release rate (HRR) and ignition time (t<sub>ig</sub>). Unmodified samples exhibited superior fire properties in terms of t<sub>ig</sub> and HRR compared to thermally modified samples. The peak heat release rate (kW.m<sup>− 2</sup>) and time to peak heat release rate (s) showed a moderate degree of dependency on the chemical constituents of the wood.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-03DOI: 10.1007/s00107-024-02085-z
Alexander Wenzel, Sergio Vera, Pablo Guindos
Location determines not only the climatic condition but also the structural loads that the structure must withstand. Given the broad variety of climatic and seismic requirements of Chile, the design of lightweight timber buildings considering both energy and seismic design parameters and boundary conditions becomes a difficult task. The main objective of this research is to analyze and quantify the effect of climates, seismic loads, lateral anchorage, and story number on the optimal energy design solutions, including the seismic behavior in a light-frame timber building. Furthermore, the optimal design was parametrically analyzed considering five Chilean cities that consider different climates, seismic zone, number of stories, and lateral anchorage systems to prevent rocking (overturning) due to lateral seismic forces. The optimal wall insulation thickness, stud spacing, and thermal mass exhibited significant variations depending on the buildings' number of stories, lateral anchorage system, climate, and seismic zone. Therefore, the results of this investigation reinforce the necessity of integrating energy and seismic designs for light-frame timber buildings. The optimal designs obtained in this investigation showed considerable variations depending on the combination of climatic and seismic loads as well as the number of stories and anchoring systems. The article's main contributions are the evidence of the structural and energy design interconnection of light-frame timber buildings and how design variables, such as stud spacing, floor concrete thickness layer, and wall insulation thickness, are related and change according to the different climates, seismic loads, lateral anchorage, and story number.
{"title":"Energy and structural optimization of mid-rise light-frame timber buildings for different climates and seismic zones in Chile","authors":"Alexander Wenzel, Sergio Vera, Pablo Guindos","doi":"10.1007/s00107-024-02085-z","DOIUrl":"https://doi.org/10.1007/s00107-024-02085-z","url":null,"abstract":"<p>Location determines not only the climatic condition but also the structural loads that the structure must withstand. Given the broad variety of climatic and seismic requirements of Chile, the design of lightweight timber buildings considering both energy and seismic design parameters and boundary conditions becomes a difficult task. The main objective of this research is to analyze and quantify the effect of climates, seismic loads, lateral anchorage, and story number on the optimal energy design solutions, including the seismic behavior in a light-frame timber building. Furthermore, the optimal design was parametrically analyzed considering five Chilean cities that consider different climates, seismic zone, number of stories, and lateral anchorage systems to prevent rocking (overturning) due to lateral seismic forces. The optimal wall insulation thickness, stud spacing, and thermal mass exhibited significant variations depending on the buildings' number of stories, lateral anchorage system, climate, and seismic zone. Therefore, the results of this investigation reinforce the necessity of integrating energy and seismic designs for light-frame timber buildings. The optimal designs obtained in this investigation showed considerable variations depending on the combination of climatic and seismic loads as well as the number of stories and anchoring systems. The article's main contributions are the evidence of the structural and energy design interconnection of light-frame timber buildings and how design variables, such as stud spacing, floor concrete thickness layer, and wall insulation thickness, are related and change according to the different climates, seismic loads, lateral anchorage, and story number.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A major function of resin in trees is to provide defense against external attacks by releasing the resin flow in the attacked or damaged area. Nonetheless, leakage of resin on the surface can have negative aesthetic and economic impacts on wood materials. The aim of this study was to investigate how heat treatment affects the physico-chemical properties of the resin of Pinus sylvestris L. to hinder exudation on wood surfaces during service. To reduce the fluidity of the resin, it is necessary to remove the volatile fraction of resin, and several studies have been carried out in this direction, providing useful information about this process. The results from thermal analyses (DSC, TGA) confirmed that heat treatment at mild temperatures, 80 °C, 90 °C and 100 °C had a positive effect on increasing the glass transition temperature Tg and that the Tg and the residual volatile content were strongly correlated. FTIR spectroscopy, before and after heat treatment, did not reveal major changes in chemical structure, while UHPLC-DAD-MS analysis revealed significant differences in the ratios of compounds, which are the result of possible chemical reactions, such as dehydrogenation, oxidation and isomerization.
{"title":"Effect of heat treatment at mild temperatures on the composition and physico-chemical properties of Scots pine resin","authors":"Errj Sansonetti, Dace Cirule, Edgars Kuka, Ingeborga Andersone, Bruno Andersons, Kristine Meile, Laima Vevere","doi":"10.1007/s00107-024-02087-x","DOIUrl":"https://doi.org/10.1007/s00107-024-02087-x","url":null,"abstract":"<p>A major function of resin in trees is to provide defense against external attacks by releasing the resin flow in the attacked or damaged area. Nonetheless, leakage of resin on the surface can have negative aesthetic and economic impacts on wood materials. The aim of this study was to investigate how heat treatment affects the physico-chemical properties of the resin of <i>Pinus sylvestris</i> L. to hinder exudation on wood surfaces during service. To reduce the fluidity of the resin, it is necessary to remove the volatile fraction of resin, and several studies have been carried out in this direction, providing useful information about this process. The results from thermal analyses (DSC, TGA) confirmed that heat treatment at mild temperatures, 80 °C, 90 °C and 100 °C had a positive effect on increasing the glass transition temperature <i>T</i><sub><i>g</i></sub> and that the <i>T</i><sub><i>g</i></sub> and the residual volatile content were strongly correlated. FTIR spectroscopy, before and after heat treatment, did not reveal major changes in chemical structure, while UHPLC-DAD-MS analysis revealed significant differences in the ratios of compounds, which are the result of possible chemical reactions, such as dehydrogenation, oxidation and isomerization.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140889902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-26DOI: 10.1007/s00107-024-02066-2
Yi Su, Jun Zou
Laminated bamboo columns with box sections are favored by designers because they overcome the disadvantage of small elastic modulus, but local buckling behavior caused by an excessive width-to-thickness ratio will lead to a non-uniform distribution of stress. The discontinuous cracks at the glued joints and waveform deformation indicate that the local buckling has a significant effect on the bearing capacity of columns with box sections. However, few studies have been reported on the evaluation of bearing capacity considering local stability due to non-uniformity and discontinuity. The experiments on 5 glued laminated bamboo columns with box sections (GLBCs) with different length-to-width ratios under axial compression were carried out. The test results showed that the waveform bulging failure occurred on the surface of GLBCs before the overall buckling, and an obvious debonding failure occurred between the bamboo plates. These failures aggravated the local buckling failure. As the length-to-width ratio increased, the number of waveforms buckling increased, the lower the bearing capacity. To evaluate the local stability of GLBCs accurately, a new anisotropic plate model considering the width correction coefficient and material anisotropy for the critical buckling load of GLBC was proposed. Furthermore, it can be found that an appropriate width-to-thickness ratio can effectively avoid local buckling failure. A formula for the critical width-to-thickness ratio of GLBCs under different slenderness ratios was proposed. In this paper, the anisotropic plate model proposed can accurately evaluate the bearing capacity considering the local stability of GLBCs under axial compression.
{"title":"Local stability of glued laminated bamboo columns with box sections under axial compression","authors":"Yi Su, Jun Zou","doi":"10.1007/s00107-024-02066-2","DOIUrl":"https://doi.org/10.1007/s00107-024-02066-2","url":null,"abstract":"<p>Laminated bamboo columns with box sections are favored by designers because they overcome the disadvantage of small elastic modulus, but local buckling behavior caused by an excessive width-to-thickness ratio will lead to a non-uniform distribution of stress. The discontinuous cracks at the glued joints and waveform deformation indicate that the local buckling has a significant effect on the bearing capacity of columns with box sections. However, few studies have been reported on the evaluation of bearing capacity considering local stability due to non-uniformity and discontinuity. The experiments on 5 glued laminated bamboo columns with box sections (GLBCs) with different length-to-width ratios under axial compression were carried out. The test results showed that the waveform bulging failure occurred on the surface of GLBCs before the overall buckling, and an obvious debonding failure occurred between the bamboo plates. These failures aggravated the local buckling failure. As the length-to-width ratio increased, the number of waveforms buckling increased, the lower the bearing capacity. To evaluate the local stability of GLBCs accurately, a new anisotropic plate model considering the width correction coefficient and material anisotropy for the critical buckling load of GLBC was proposed. Furthermore, it can be found that an appropriate width-to-thickness ratio can effectively avoid local buckling failure. A formula for the critical width-to-thickness ratio of GLBCs under different slenderness ratios was proposed. In this paper, the anisotropic plate model proposed can accurately evaluate the bearing capacity considering the local stability of GLBCs under axial compression.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140802740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-26DOI: 10.1007/s00107-024-02078-y
Oktay Gonultas
The study addresses concerns associated with formaldehyde-based adhesives in wood panel board production by proposing geopolymer-based wood binders as promising, formaldehyde-free alternatives. Using bentonite, the research delves into the development and performance properties of this geopolymer wood binder. The BET method was employed for the surface characterization of precursor raw materials for binder preparation. Si and Al elements identified through XRF analysis were correlated with characteristic bands in the FTIR spectrum. Alkaline activation solutions, employing sodium silicate and sodium hydroxide with a molar ratio range of 0.5 to 2.5 (SiO2:Na2O), revealed that binders with a molar ratio of 2.5 exhibited lower pH and higher adhesion strength. Different geopolymer formulations at solution to powder ratios (s/p) of 1.33, 3, and 3.5 determined s/p 3.5 as optimal for bentonite-based organo-geopolymer binders. Viscosity, gel time, pH, and solids content were examined, showing the effectiveness of substituting 10% silica fume to enhance the geopolymerization process and improve adhesion. Modifications using citric acid, sucrose, paraffin, pMDI, triacetin, and resorcinol demonstrated wet bonding strength comparable to urea formaldehyde adhesive. Analytical techniques, including FTIR spectroscopy, XRD analysis, and SEM EDX analysis, provided insights into functional groups, crystallographic properties, and microstructural characteristics. The concentration of Si and Al compounds on the bonding line, coupled with Na element diffusion, was observed through these analyses. Light microscopy of lap shear samples revealed a thinner bonding line, affirming effective binder penetration into wood cell lumens in bentonite-based organo-geopolymer binder formulations.
该研究提出了以土工聚合物为基础的木材粘合剂作为前景广阔的无甲醛替代品,从而解决了人造板生产中与甲醛基粘合剂相关的问题。研究使用膨润土,深入探讨了这种土工聚合物木材粘合剂的开发和性能特性。研究采用 BET 方法对制备粘合剂的前体原材料进行表面表征。通过 XRF 分析确定的硅和铝元素与傅立叶变换红外光谱中的特征谱带相关联。采用硅酸钠和氢氧化钠摩尔比范围为 0.5 至 2.5(SiO2:Na2O)的碱性活化溶液显示,摩尔比为 2.5 的粘结剂具有较低的 pH 值和较高的粘结强度。溶液与粉末的比率(s/p)分别为 1.33、3 和 3.5 时,不同的土工聚合物配方确定 s/p 3.5 为膨润土基有机土工聚合物粘结剂的最佳比率。对粘度、凝胶时间、pH 值和固体含量进行了检测,结果表明用 10% 的硅灰替代硅粉可有效增强土工聚合过程并提高粘附性。使用柠檬酸、蔗糖、石蜡、pMDI、三醋精和间苯二酚进行改性后,湿粘合强度与脲醛粘合剂相当。傅立叶变换红外光谱、XRD 分析和 SEM EDX 分析等分析技术有助于深入了解官能团、晶体学特性和微观结构特征。通过这些分析,可以观察到结合线上硅和铝化合物的浓度,以及 Na 元素的扩散情况。搭接剪切样品的光学显微镜检查发现,粘合线更细,这证明膨润土基有机土工聚合物粘合剂配方中的粘合剂能有效渗入木材细胞腔。
{"title":"Development of bentonite-based organo-geopolymer hybrid wood binder","authors":"Oktay Gonultas","doi":"10.1007/s00107-024-02078-y","DOIUrl":"https://doi.org/10.1007/s00107-024-02078-y","url":null,"abstract":"<p>The study addresses concerns associated with formaldehyde-based adhesives in wood panel board production by proposing geopolymer-based wood binders as promising, formaldehyde-free alternatives. Using bentonite, the research delves into the development and performance properties of this geopolymer wood binder. The BET method was employed for the surface characterization of precursor raw materials for binder preparation. Si and Al elements identified through XRF analysis were correlated with characteristic bands in the FTIR spectrum. Alkaline activation solutions, employing sodium silicate and sodium hydroxide with a molar ratio range of 0.5 to 2.5 (SiO<sub>2</sub>:Na<sub>2</sub>O), revealed that binders with a molar ratio of 2.5 exhibited lower pH and higher adhesion strength. Different geopolymer formulations at solution to powder ratios (s/p) of 1.33, 3, and 3.5 determined s/p 3.5 as optimal for bentonite-based organo-geopolymer binders. Viscosity, gel time, pH, and solids content were examined, showing the effectiveness of substituting 10% silica fume to enhance the geopolymerization process and improve adhesion. Modifications using citric acid, sucrose, paraffin, pMDI, triacetin, and resorcinol demonstrated wet bonding strength comparable to urea formaldehyde adhesive. Analytical techniques, including FTIR spectroscopy, XRD analysis, and SEM EDX analysis, provided insights into functional groups, crystallographic properties, and microstructural characteristics. The concentration of Si and Al compounds on the bonding line, coupled with Na element diffusion, was observed through these analyses. Light microscopy of lap shear samples revealed a thinner bonding line, affirming effective binder penetration into wood cell lumens in bentonite-based organo-geopolymer binder formulations.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140802803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-25DOI: 10.1007/s00107-024-02081-3
Roberto D. Martínez, M. Casado, L. Basterra
{"title":"Protective role of DTPA against Hylotrupes bajulus L. infestations by targeting metal ion incorporation in larval mandibles","authors":"Roberto D. Martínez, M. Casado, L. Basterra","doi":"10.1007/s00107-024-02081-3","DOIUrl":"https://doi.org/10.1007/s00107-024-02081-3","url":null,"abstract":"","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140655789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-23DOI: 10.1007/s00107-024-02080-4
Tomáš Pipíška, Marek Nociar, Pavel Král, Jozef Ráheľ, Pavlo Bekhta, R. Réh, Ľ. Krišťák, Miroslav Jopek, Barbora Pijáková, Rupert Wimmer, Milan Šernek
{"title":"Characterization of randomly oriented strand boards manufactured from juvenile wood of underutilized wood species","authors":"Tomáš Pipíška, Marek Nociar, Pavel Král, Jozef Ráheľ, Pavlo Bekhta, R. Réh, Ľ. Krišťák, Miroslav Jopek, Barbora Pijáková, Rupert Wimmer, Milan Šernek","doi":"10.1007/s00107-024-02080-4","DOIUrl":"https://doi.org/10.1007/s00107-024-02080-4","url":null,"abstract":"","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140671993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-22DOI: 10.1007/s00107-024-02077-z
G. Pot, Robin Duriot, Stéphane Girardon, J. Viguier, L. Denaud
{"title":"Correction: Comparison of classical beam theory and finite element modelling of timber from fibre orientation data according to knot position and loading type","authors":"G. Pot, Robin Duriot, Stéphane Girardon, J. Viguier, L. Denaud","doi":"10.1007/s00107-024-02077-z","DOIUrl":"https://doi.org/10.1007/s00107-024-02077-z","url":null,"abstract":"","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140677797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-22DOI: 10.1007/s00107-024-02071-5
Rahat Mahmud Khan, Marcus S. Dersch, Alison C. Dunn
Elastic fasteners have been widely adopted in timber sleeper tracks in certain high-demand areas across North American freight network due to their excellent potential to mitigate rail-rollover derailments by resisting steering moment and rotation of rail from the vertical axis through intense elastic force to securely hold-down the rail to the sleeper baseplate. However, these systems have led to at least 13 derailments reported since 2000 because of sleeper baseplate spike fatigue failures. Previous spike-failure investigations established that the loss of friction at the baseplate-sleeper interface caused by the wave-action of rail was the major mechanism that transfers additional loads to the spikes, and results in spike stresses exceeding the endurance limits. Previous studies also demonstrated the positives of plate hold-down load on controlling spike stress levels; with this load being historically applied via spring washers. Although the static performance of such hold-down systems has been evaluated in the literature, the long-term, time dependent behavior has not been quantified previously. This paper quantifies the effects of timber sleeper species, spring washer resiliency, and installation load on stress relaxation of these systems over 1,000 h in the laboratory under constant climate conditions. Experimental data demonstrate the significant impact of installation load magnitude on relaxation performance – load retention of 96% and 67% observed under 11.1 kN (2,500 lbs.) and 66.7 kN (15,000 lbs.) installation load, respectively. However, the insignificant effect of spring resiliency on the relaxation behavior was reflected through a 2% only change in load retention over a four-fold change in resiliency. A 15% increase in load retention was achieved by using Red Oak in place of Mixed Hardwood which established sleeper species as a critical parameter in such applications. An assessment of an extended experimentation period (i.e., 2,450 h) was carried out to better estimate the end point of relaxation. The experiments were conducted in an environmental chamber that does not represent the harsh conditions (i.e., loads, vibrations, temperature, humidity, or moisture) of the revenue-service tracks. However, results from this work can reasonably be useful to guide the selection of appropriate components along with recommended installation loads for hold-down applications to improve the overall safety of timber sleeper tracks that leverage elastic fasteners.
{"title":"Quantification of stress relaxation in a timber fastening system: a railway focused study","authors":"Rahat Mahmud Khan, Marcus S. Dersch, Alison C. Dunn","doi":"10.1007/s00107-024-02071-5","DOIUrl":"https://doi.org/10.1007/s00107-024-02071-5","url":null,"abstract":"<p>Elastic fasteners have been widely adopted in timber sleeper tracks in certain high-demand areas across North American freight network due to their excellent potential to mitigate rail-rollover derailments by resisting steering moment and rotation of rail from the vertical axis through intense elastic force to securely hold-down the rail to the sleeper baseplate. However, these systems have led to at least 13 derailments reported since 2000 because of sleeper baseplate spike fatigue failures. Previous spike-failure investigations established that the loss of friction at the baseplate-sleeper interface caused by the wave-action of rail was the major mechanism that transfers additional loads to the spikes, and results in spike stresses exceeding the endurance limits. Previous studies also demonstrated the positives of plate hold-down load on controlling spike stress levels; with this load being historically applied via spring washers. Although the static performance of such hold-down systems has been evaluated in the literature, the long-term, time dependent behavior has not been quantified previously. This paper quantifies the effects of timber sleeper species, spring washer resiliency, and installation load on stress relaxation of these systems over 1,000 h in the laboratory under constant climate conditions. Experimental data demonstrate the significant impact of installation load magnitude on relaxation performance – load retention of 96% and 67% observed under 11.1 kN (2,500 lbs.) and 66.7 kN (15,000 lbs.) installation load, respectively. However, the insignificant effect of spring resiliency on the relaxation behavior was reflected through a 2% only change in load retention over a four-fold change in resiliency. A 15% increase in load retention was achieved by using Red Oak in place of Mixed Hardwood which established sleeper species as a critical parameter in such applications. An assessment of an extended experimentation period (i.e., 2,450 h) was carried out to better estimate the end point of relaxation. The experiments were conducted in an environmental chamber that does not represent the harsh conditions (i.e., loads, vibrations, temperature, humidity, or moisture) of the revenue-service tracks. However, results from this work can reasonably be useful to guide the selection of appropriate components along with recommended installation loads for hold-down applications to improve the overall safety of timber sleeper tracks that leverage elastic fasteners.</p>","PeriodicalId":550,"journal":{"name":"European Journal of Wood and Wood Products","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140636857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}